On Tue, 18 Apr 2023, Ville Syrjala ville.syrjala@linux.intel.com wrote:

From: Ville Syrjälä ville.syrjala@linux.intel.com

The skl+ scalers only sample 12 bits of PIPESRC so we can't do any plane scaling at all when the pipe source size is >4k.

Make sure the pipe source size is also below the scaler's src size limits. Might not be 100% accurate, but should at least be safe. We can refine the limits later if we discover that recent hw is less restricted.

Cc: stable@vger.kernel.org Tested-by: Ross Zwisler zwisler@google.com Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/8357 Signed-off-by: Ville Syrjälä ville.syrjala@linux.intel.com

Reviewed-by: Jani Nikula jani.nikula@intel.com

---

drivers/gpu/drm/i915/display/skl_scaler.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+)

diff --git a/drivers/gpu/drm/i915/display/skl_scaler.c b/drivers/gpu/drm/i915/display/skl_scaler.c index 473d53610b92..0e7e014fcc71 100644 --- a/drivers/gpu/drm/i915/display/skl_scaler.c +++ b/drivers/gpu/drm/i915/display/skl_scaler.c @@ -111,6 +111,8 @@ skl_update_scaler(struct intel_crtc_state *crtc_state, bool force_detach, struct drm_i915_private *dev_priv = to_i915(crtc->base.dev); const struct drm_display_mode *adjusted_mode = &crtc_state->hw.adjusted_mode;

• int pipe_src_w = drm_rect_width(&crtc_state->pipe_src);
• int pipe_src_h = drm_rect_height(&crtc_state->pipe_src); int min_src_w, min_src_h, min_dst_w, min_dst_h; int max_src_w, max_src_h, max_dst_w, max_dst_h;

@@ -207,6 +209,21 @@ skl_update_scaler(struct intel_crtc_state *crtc_state, bool force_detach, return -EINVAL; }

• /*

• * The pipe scaler does not use all the bits of PIPESRC, at least
  

• * on the earlier platforms. So even when we're scaling a plane
  

• * the *pipe* source size must not be too large. For simplicity
  

• * we assume the limits match the scaler source size limits. Might
  

• * not be 100% accurate on all platforms, but good enough for now.
  

• */
  

• if (pipe_src_w > max_src_w || pipe_src_h > max_src_h) {

• drm_dbg_kms(&dev_priv->drm,
  

• 	    "scaler_user index %u.%u: pipe src size %ux%u "
  

• 	    "is out of scaler range\n",
  

• 	    crtc->pipe, scaler_user, pipe_src_w, pipe_src_h);
  

• return -EINVAL;
  

• }
• /* mark this plane as a scaler user in crtc_state */ scaler_state->scaler_users |= (1 << scaler_user); drm_dbg_kms(&dev_priv->drm, "scaler_user index %u.%u: "